It is 01.00am and a 30-year-old male has presented to the ED after falling over whilst intoxicated with alcohol. He has dislocated the proximal inter-phalangeal joint of his right index finger. The dislocation is grossly displaced and he is very distressed. He is requesting that he be 'knocked out' to have it relocated as a previous nail bed repair performed under digital nerve block was very painful.
The senior ED staff are occupied with a major trauma patient who has just arrived in the resuscitation room.
List three reasons why intravenous sedation may not be suitable for this patient.